THR Nominees Night 2014: What Leonardo DiCaprio, Lupita Nyong'o Wore to the Party (Video)

The evening's guests -- also including Jared Leto, David O. Russell, Ethan Hawke and Julie Delpy -- dished on what they wore to the star-studded bash on Monday at Beverly Hills' Spago.

In anticipation to what this year's Oscars nominees will wear when they hit the red carpet on March 2, we asked what Hollywood's biggest stars donned at The Hollywood Reporter's Nominees Night party on Monday at Beverly Hills hotspot Spago.

Before Midnight nominee Ethan Hawke (in Dior) joked that his co-star Julie Delpy (in Oliver Tolentino) arrived to the scene "without any underwear." Delpy differed, however, responding: "Oh no, I always wear underwear. I hate going without underwear. It's my thing."

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American Hustle director David O. Russell -- who was recently featured as THR's cover star and revealed that he owned five identical three-piece suits from J. Crew -- arrived in a suit designed by the American brand, natch.

12 Years a Slave nominee and fashion's newest "it" girl Lupita Nyong'o stunned in a gold Valentino Couture gown, telling THR awards analyst Scott Feinberg, "Of course [it's fun to wear the dress.]" She added, "I'm asking Pharrell [Williams] if I can borrow his hat for the Oscars."

Dallas Buyers Club nominee Jared Leto -- who arrived in a sleek silver Lanvin blazer -- joked about how his black topper "is half the hat of Pharrell. He has a five-gallon hat; this is … two gallons."

Another A-lister to arrive to the scene was Leonardo DiCaprio, who stayed true to his Wolf of Wall Street character by wearing "Giorgio Armani, [a] true Jordan Belfort outfit."

The Nominees Night party was hosted by Janice Min, co-president/chief creative officer of the Entertainment Group of Guggenheim Media, and Lynne Segall, THR senior vp and publisher. It came hours after Nyong'o and other top talent attended the Academy of Motion Picture Arts and Sciences nominees luncheon, where the annual class photo was taken of all of this year's nominees.

For more on THR's Nominees Night party, including exclusive video and photos, click here.